# Light Year Sphere

Lets say you had a sphere that was a light year in diameter, could it be moved at all? For in order for it to begin to move wouldn’t it take a light year for all the energy put to it to get to the other end thus to allow it to move…or would we actually be able to create enough energy to move it, could anything for that matter? Wouldn’t that suggest a maximum size of a mass. and also if it actually couldn’t move, then would it be instantly gone? For everything else is constantly moving if it was staying perfectly still: it may not move instantly but really fast unless some how we could be sure that we were not moving…but if you were an observer of it from earth it would at least be almost instantly gone, sense the earth is moving around the sun and the sun around our galaxy and the galaxy is moving…etc

Not and remain a perfect sphere during the movement (or when you starting moving it).

Exactly.

Not enough information for that.

What it means is that you can’t maintain a perfect sphere while you begin to move it.
Once you got it moving, or if it was formed already in motion, it would stay a sphere until it moved differently.

I recognize what you said but another thought popped into my head. Because it is a sphere wouldn’t there be equal resistance to it displacing in all directions. as such it would not be able to displace to allow movement to begin or transfer throughout…

What is the significance in it being a big ball instead of a small ball?
If you could displace one, why couldn’t you displace the other?

The limit of light speed might have an effect hear is what I’m thinking…IDK
It doesn’t really matter because creating one would be ridiculously hard, there doesn’t seem to be a reason to do so, and i think if we did and it was actually immobile that would be potentially extremely dangerous.

You push one molecule and it pushes on the next etc. and in a solid they are almost locked in place
The energy doesn’t travel across the entire sphere it travels from the pushing force to the object so in theory you could move it.
The sphere would compress when you accelerated it but once it moved with constant speed it would return to the spherical shape.
This is all assuming my knowledge of physics is correct.

If you pushed a 1 light year diameter sphere on one end it would take pi/2 years for the effect to propagate to the front and for the front to start moving. The back would be distorted and the amount of distortion would depend on the force applied and the material and mass of the sphere. The entire sphere would be moving after pi/2 years if it didn’t break. Energy required would depend on the mass.

Well what I was thinking is that in order for motion to start the atoms makeing up the thing would have to be able to be displaced. In order to move in the direction you push the atoms would have to displace other atoms in the directions perpindicular to the pushing force, but in order for the displacement to occur in the perpendicular direction there would have to be displacement in the forwrd pushing diretion. As such it would seem the thing would be un movable in that no displacement would occur, due to the recistance caused by the light year distance all across…That was my thought but then I realized that it would not displace in the distance from one center side to the next, the displacement would begin near the point where you pushed such that perpindicular to the force exerted there, that single portion of the circle would be displace, and that portion would not be one light year across. You might be able to conceptualize the idea of an object that is a light year across in all ways, from all points to all other sides, but such an object is not actually possible, or so it would seem, unless that object was perhaps in fact of an infinite nature such as perhaps the universe as a whole or something…